Reviewing the use of resilience concepts in forest sciences

Purpose of the review Resilience is a key concept to deal with an uncertain future in forestry. In recent years, it has received increasing attention from both research and practice. However, a common understanding of what resilience means in a forestry context, and how to operationalise it is lacking. Here, we conducted a systematic review of the recent forest science literature on resilience in the forestry context, synthesising how resilience is defined and assessed. Recent findings Based on a detailed review of 255 studies, we analysed how the concepts of engineering resilience, ecological resilience, and social-ecological resilience are used in forest sciences. A clear majority of the studies applied the concept of engineering resilience, quantifying resilience as the recovery time after a disturbance. The two most used indicators for engineering resilience were basal area increment and vegetation cover, whereas ecological resilience studies frequently focus on vegetation cover and tree density. In contrast, important social-ecological resilience indicators used in the literature are socio-economic diversity and stock of natural resources. In the context of global change, we expected an increase in studies adopting the more holistic social-ecological resilience concept, but this was not the observed trend. Summary Our analysis points to the nestedness of these three resilience concepts, suggesting that they are complementary rather than contradictory. It also means that the variety of resilience approaches does not need to be an obstacle for operationalisation of the concept. We provide guidance for choosing the most suitable resilience concept and indicators based on the management, disturbance and application context

Simulation of powder avalanches by FIRE ; Verification of results on example of Wolfsgruben avalanche (march 1988) in St Anton Tyrol Austria

The application of the AVL-powder-avalanche model, the comparison between the results of this numerical model an the mapped damages are demonstrated to the Wolfsgruben avalanche disaster in St. Anton (March 1988) in Tyrol/Austria. / L'application du modèle AVL d'avalanche poudreuse et la comparaison entre les résultats obtenus par ce modèle numérique et les dégâts cartographiés sont présentés dans le cas particulier de l'accident de l'avalanche de Wolfsgruben, à Saint Anton dans le Tyrol, en Autriche

Metallurgical and mechanical properties of thorium-doped Ir-0. 3% W alloys

Metallurgical and mechanical properties of Ir-0.3% W alloys have been studied as a function of thorium concentration in the range 0 to 1000 ppM by weight. The solubility limit of thorium in Ir-0.3% W is below 30 ppM. Above this limit, the excess thorium reacts with iridium to form second-phase particles. Thorium additions raise the recrystallization temperature and effectively retard grain growth at high temperatures. Tensile tests at 650/sup 0/C show that the alloy without thorium additions (undoped alloy) fractured by grainboundary (GB) separation, while the alloys doped with less than 500 ppM thorium failed mainly by transgranular fracture at 650/sup 0/C. Intergranular fracture in the doped alloys is suppressed by GB segregation of thorium, which improves the mechanical properties of the boundary. The impact properties of the alloys were correlated with test temperature, grain size, and heat treatment. The impact ductility increases with test temperature and decreases with grain size. For a given grain size, particularly in the fine-grain size range, the thorium-doped alloys are much more ductile and resistant to GB fracture. All of these results can be correlated on the basis of stress concentration on GBs by using a dislocation pileup model

User Acceptance of Mobile Technology: A Campus-Wide Implementation of Blackboard's Mobile™ Learn Application

Mobile learning is a fast growing trend in higher education. This study examined how an extended technology acceptance model (TAM) could evaluate and predict the use of a mobile application in learning. A path analysis design was used to measure the mediating effects on the use of Blackboard\u27s Mobile TM Learn application in coursework (N = 77). The results indicate that the hypothesized model was a strong fit, x2(8, N = 77) = 6.84, p = 0.55. Perceived resources, perceived ease of use, perceived usefulness, and attitude were found to be significant determinants of users\u27 acceptance of mobile application technology. The findings of this research have implications for educational leaders, mobile application designers, course instructors, and instructional technologists who want to understand why students adopt mobile learning, how to devise practical methods for integrating mobile applications into curriculum, and ways to evaluate of the acceptance and usability of the mobile learning systems